Ntp
CVE-2016-1550
MEDIUM
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A01:2025 - Broken Access Control
ASVS 5.0
V14 - Data Protection Data exposure prevention
MITRE ATT&CK
2 techniques across 2 tactics: Collection, Discovery The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. |
| Impact | CVSS score of 5.3 (MEDIUM). Attack characteristics: network attack vector, low complexity, no privileges required, no user interaction not required. EPSS exploitation probability: 3.13%. |
| Exploit ScenarioDerived | A remote attacker could access sensitive data that should not be disclosed by sending crafted requests to the affected application. No authentication is required to exploit this vulnerability. |
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Alert meAnalysisAI
An exploitable vulnerability exists in the message authentication functionality of libntp in ntp 4.2.8p4 and NTPSec a5fb34b9cc89b92a8fef2f459004865c93bb7f92. Rated medium severity (CVSS 5.3), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
RemediationAI
No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Minimize information in error messages, implement proper access controls, encrypt sensitive data at rest and in transit.
Affects your stack
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Checking this CVE against your own stacks and servers is part of the Basic plan and up.
Technical ContextAI · show details
This vulnerability is classified as Exposure of Sensitive Information (CWE-200), which allows attackers to access sensitive data that should not be disclosed. An exploitable vulnerability exists in the message authentication functionality of libntp in ntp 4.2.8p4 and NTPSec a5fb34b9cc89b92a8fef2f459004865c93bb7f92. An attacker can send a series of crafted messages to attempt to recover the message digest key. Affected products include: Ntp.
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- Exploit and PoC references, threat intelligence from 22 sources
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Severity by source
AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
DescriptionCVE.org
An exploitable vulnerability exists in the message authentication functionality of libntp in ntp 4.2.8p4 and NTPSec a5fb34b9cc89b92a8fef2f459004865c93bb7f92. An attacker can send a series of crafted messages to attempt to recover the message digest key.
Threat Intelligence Overview
NVD
CVE.org
EPSS
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Information disclosure occurs when an application unintentionally exposes sensitive data that aids attackers in reconnaissance or directly compromises security.
Affected Products (CPE)CVE.org
Crypto-NAK packets in ntpd in NTP 4.2.x before 4.2.8p4, and 4.3.x before 4.3.77 allows remote attackers to bypass authen
The monlist feature in ntp_request.c in ntpd in NTP before 4.2.7p26 allows remote attackers to cause a denial of service
The read_mru_list function in NTP before 4.2.8p9 allows remote attackers to cause a denial of service (crash) via a craf
The decodenetnum function in ntpd in NTP 4.2.x before 4.2.8p4, and 4.3.x before 4.3.77 allows remote attackers to cause
Multiple stack-based buffer overflows in ntpd in NTP before 4.2.8 allow remote attackers to execute arbitrary code via a
ntpd in NTP before 4.2.8p8 allows remote attackers to cause a denial of service (daemon crash) via a crypto-NAK packet.
util/ntp-keygen.c in ntp-keygen in NTP before 4.2.7p230 uses a weak RNG seed, which makes it easier for remote attackers
The config_auth function in ntpd in NTP before 4.2.7p11, when an auth key is not configured, improperly generates a key,
The datalen parameter in the refclock driver in NTP 4.2.x before 4.2.8p4, and 4.3.x before 4.3.77 allows remote attacker
NTP before 4.2.8p6 and 4.3.0 before 4.3.90 allows a remote attackers to cause a denial of service (stack exhaustion) via
The rate limiting feature in NTP 4.x before 4.2.8p4 and 4.3.x before 4.3.77 allows remote attackers to have unspecified
The panic_gate check in NTP before 4.2.8p5 is only re-enabled after the first change to the system clock that was greate
GitHub PoC
Exploit-DB